Mallory Book is one of She-Hulk's co-workers.
Mallory Book's legal skills are like her beauty---impressive and intimidating. As a student at BYU, she managed to win the title of Miss Utah in a beauty contest while graduating at the top of her class, summa cum laude. With the top law firms in the country begging for her services, she chose to join Goodman, Lieber, Kurtzberg, & Holliway, not just because it was the most prestigious law firm on the East Coast, but she was excited about the new field of "superhuman law" and working for the great Holden Holliway. The firm's confidence in Ms. Book was not misplaced as she quickly earned the nickname in legal circles as "the face who never lost a case." She first clashed with Jennifer Walters (She-Hulk) when the latter was working for the New York District Attorney office. Mallory's client was charged with improperly storing Antarctic Vibranium, which caused a warehouse collapse. Walters won a huge settlement for the state, but Book successfully overturned the judgement on appeal, arguing that by saving the Earth as an Avenger, She-Hulk had biased the jury in her favor. This loss led to Walters' dismissal from the D.A. office where she was hired by GLK&H, on the condition she work for them in human form rather than as She-Hulk.
Mallory unintentionally helped Jennifer adjust to these new conditions, which she was highly resentful of at first. Book had little respect for Jen's legal skills and thought her only value to the firm was her physical abilities as She-Hulk as well as her many connections in the superhuman community. So when Mallory was assigned to a high-profile murder case where her defense rested on calling upon the victim's ghost as a witness, she specifically requested that Jen Walters be assigned as her second so she could get her friend the Ben Grimm (the Thing) to testify, since he had recently come back from the dead. Despite Mallory's permission to "hulk out", Jen refused and managed to get the ghost's testimony admitted when Mallory's plan of attack failed.
Her relationship with Jen Walters deteriorated further when Mallory was defending Hercules in a civil lawsuit brought on by the villain Constrictor for excessive force. The case could have been easily won if Herc had only heeded Mallory's advice, but he repeatedly managed to undermine her arguments. Finally, Jen Walters urged Hercules to accept responsibility for his actions and settle the lawsuit, thus ending Mallory's unbeaten streak in court. This greatly upset Mallory, and led to a performance review by not only Holden Holliway, but the other (and rarely seen) senior partners of the law firm, Martin Goodman, Stanley Lieber, and Jacob Kurtzberg. It was during this review that Titania attacked Timely Plaza in search of She-Hulk. Mallory was crippled in the attack and left a paraplegic. Holding Jen Walters personally responsible for both her one legal defeat as well as her injuries, Mallory has decided to get back at Jen by taking advantage of the precedent of her loss and agressively encourage supervillains to sue superheroes. Furthermore, she has spread word throughout the superhero community that Jen Walters is responsible for this change. This has led to a strain in Jennifer's relationship with her superhero allies, including Ben Grimm. The new acting head of the superhuman legal division at GLK&H, Arthur Zix has supported Mallory's decision, which has made things very uncomfortable for Jennifer at work.